#!/usr/bin/perl
use warnings;
use Data::Dumper;
use strict;
my %a = (a => 'b', c => [qw/user1 user2 user3/], e => 'f');
my %b = reverse %a;
print Dumper(\%b);

$VAR1 = {
          'f' => 'e',
          'b' => 'a',
          'ARRAY(0x81522d8)' => 'c'
        };